1. Field of the Invention
This invention relates to a stirrer which is useful particularly in pharmaceutical, food and chemical industries for mixing, dissolving, kneading and diffusing a liquid or other material in a container.
2. Discussion of the Background
Illustrated in FIG. 30 is a known mixer which is provided with a stirring vessel a, a rotational transmission c located externally under the bottom wall of the stirring vessel a and driven from an electric motor b, and an impeller shaft e which protrudes from below into a lower portion of the vessel a and having impeller vanes d. The impeller shaft e and the transmission c are coupled to each other through a magnetic coupling f to rotate the impeller wheel d.
This sort of conventional stirrer is required to separately provide a rotational drive like the motor b for rotating the impeller vanes d which invariably have drawbacks in that they are of complex construction and are large in size.